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COLOR MONITORSERVICE MANUAL
Website:http://biz.LGservice.comE-mail:http://www.LGEservice.com/techsup.html
CAUTION
BEFORE SERVICING THE UNIT,READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
CHASSIS NO. : LM57A
MODEL: L1919S (L1919S-SFQ.A**REP,A**XEP,AX**EP)
*To apply the MSTAR Chip.
( ) **Same model for Service
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CONTENTS
1. LCD CHARACTERISTICSType : TFT Color LCD ModuleActive Display Area : 19 inchPixel Pitch : 0.294 (H) x 0.294 (V)Color Depth : 8bits, 16.2M colorsSize : 396 (H) x 324 (V) x 17.5(D)
Electrical Interface : LVDSSurface Treatment : Hard-coating(3H), Anti-GlareOperating Mode : Normally White, Transmissive modeBacklight Unit : 4-CCFL
2. OPTICAL CHARACTERISTICS2-1. Viewing Angle by Contrast Ratio 10
Left : -70min., -80(Typ) Right : +70min., +80(Typ)Top :+60min., +75(Typ) Bottom : -70min., -85(Typ)
2-2. Luminance : 250(min), 300(Typ) (Full White pattern, 0.7V) -6500K: 150(min) (Full White pattern, 0.7V) -9300K
2-3. Contrast Ratio : 500(min), 700(Tye)
3. SIGNAL (Refer to the Timing Chart)3-1. Sync Signal
Type : Separate Sync, SOG
3-2. Video Input Signal1) Type : R, G, B Analog2) Voltage Level : 0~0.71 Va) Color 0, 0 : 0 Vp-pb) Color 7, 0 : 0.467Vp-pc) Color 15, 0 : 0.714Vp-p
3) Input Impedance : 75
3-3. Operating FrequencyHorizontal : 30 ~ 83kHzVertical : 56 ~ 75Hz
4. Max. ResolutionD-sub Analog : 1280 x 1024@75Hz
5. POWER SUPPLY5-1. Power : AC 100~240V, 50/60Hz , 0.8A
5-2. Power Consumption
6. ENVIRONMENT6-1. Operating Temperature : 10C~35C (50F~95F)
(Ambient)6-2. Relative Humidity : 10%~80% (Non-condensing)6-3. MTBF : 50,000 HRS with 90% Confidence
Lamp Life : 50,000 Hours(Min)
7. DIMENSIONS (with TILT/SWIVEL)
Width : 414.15 mm (16.31'')Depth : 180.3 mm (7.10'')Height : 413.2 mm (16.27'')
8. WEIGHT (with TILT/SWIVEL)
Net. Weight : 4.23 kg (9.33 lbs)
Gross Weight : 5.22 kg (11.51 lbs)
SPECIFICATIONS
SPECIFICATIONS ................................................... 2
PRECAUTIONS ....................................................... 3
TIMING CHART ....................................................... 7
DISASSEMBLY ........................................................ 8
BLOCK DIAGRAM...................................................10
DISCRIPTION OF BLOCK DIAGRAM .................. 12
ADJUSTMENT ...................................................... 14
SERVICE OSD ........................................................15
TROUBLESHOOTING GUIDE .............................. 16
WIRING DIAGRAM ............................................... 22
EXPLODED VIEW...................................................23
REPLACEMENT PARTS LIST ...............................25
SCHEMATIC DIAGRAM......................................... 29
MODE
POWER ON (NORMAL)
STAND-BY
SUSPEND
DPMS OFF
POWER S/W OFF
H/V SYNC
ON/ON
OFF/ON
ON/OFF
OFF/OFF
-
POWER CONSUMPTION
less than 33 W
less than 1 W
less than 1 W
less than 1 W
less than 1 W
LED COLOR
GREEN
AMBER
AMBER
AMBER
OFF
VIDEO
ACTIVE
OFF
OFF
OFF
-
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PRECAUTION
WARNING FOR THE SAFETY-RELATED COMPONENT.
There are some special components used in LCD
monitor that are important for safety. These parts are
marked on the schematic diagram and the
replacement parts list. It is essential that these critical
parts should be replaced with the manufacturers
specified parts to prevent electric shock, fire or other
hazard.
Do not modify original design without obtaining written
permission from manufacturer or you will void the
original parts and labor guarantee.
TAKE CARE DURING HANDLING THE LCD MODULE
WITH BACKLIGHT UNIT.
Must mount the module using mounting holes arranged
in four corners. Do not press on the panel, edge of the frame strongly
or electric shock as this will result in damage to the
screen.
Do not scratch or press on the panel with any sharp
objects, such as pencil or pen as this may result in
damage to the panel.
Protect the module from the ESD as it may damage the
electronic circuit (C-MOS).
Make cer tain that t reatment persons body are
grounded through wrist band.
Do not leave the module in high temperature and in
areas of high humidity for a long time.
The module not be exposed to the direct sunlight.
Avoid contact with water as it may a short circuit within
the module.
If the surface of panel become dirty, please wipe it off
with a softmaterial. (Cleaning with a dirty or rough cloth
may damage the panel.)
WARNING
BE CAREFUL ELECTRIC SHOCK !
If you want to replace with the new backlight (CCFL) or
inverter circuit, must disconnect the AC adapter
because high voltage appears at inverter circuit about650Vrms.
Handle with care wires or connectors of the inverter
circuit. If the wires are pressed cause short and may
burn or take fire.
Leakage Current Hot Check Circuit
CAUTION
Please use only a plastic screwdriver to protect yourselffrom shock hazard during service operation.
1.5 Kohm/10W
To InstrumentsexposedMETALLIC PARTS
Good Earth Groundsuch as WATER PIPE,CONDUIT etc.
AC Volt-meter
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SERVICING PRECAUTIONS
CAUTION: Before servicing receivers covered by thisservice manual and its supplements and addenda, read
and follow the SAFETY PRECAUTIONSon page 3 of thispublication.NOTE: I f unforeseen c i rcumstances create conf l ic t
between the following servicing precautions and any of thesafety precautions on page 3 of this publication, alwaysfollow the safety precautions. Remember: Safety First.
General Servicing Precautions
1. Always unplug the receiver AC power cord from the ACpower source before;
a. Removing or reinstalling any component, circuitboard module or any other receiver assembly.
b. Disconnecting or reconnecting any receiver electricalplug or other electrical connection.
c. Connecting a test substitute in parallel with an
electrolytic capacitor in the receiver.CAUTION: A wrong part substitution or incorrect
polarity installation of electrolytic capacitors mayresult in an explosion hazard.
d. Discharging the picture tube anode.2. Test high voltage only by measuring i t with an
appropriate high voltage meter or other voltage
measuring device (DVM, FETVOM, etc) equipped witha suitable high voltage probe.
Do not test high voltage by "drawing an arc".3. Discharge the picture tube anode only by (a) first
connecting one end of an insulated clip lead to thedegaussing or kine aquadag grounding system shieldat the point where the picture tube socket ground lead
is connected, and then (b) touch the other end of the
insulated clip lead to the picture tube anode button,using an insulating handle to avoid personal contactwith high voltage.
4. Do not spray chemicals on or near this receiver or any
of its assemblies.5. Unless specified otherwise in this service manual,
clean electrical contacts only by applying the followingmixture to the contacts with a pipe cleaner, cotton-
tipped stick or comparable non-abrasive applicator;10% (by volume) Acetone and 90% (by volume)isopropyl alcohol (90%-99% strength)CAUTION: This is a flammable mixture.Unless specified otherwise in this service manual,
lubrication of contacts in not required.6. Do not defeat any plug/socket B+ voltage interlocks
with which receivers covered by this service manualmight be equipped.
7. Do not apply AC power to this instrument and/or any of
its electrical assemblies unless all solid-state deviceheat sinks are correctly installed.
8. Always connect the test receiver ground lead to thereceiver chassis ground before connecting the test
receiver positive lead.Always remove the test receiver ground lead last.
9. Use with this receiver only the test fixtures specified inthis service manual.CAUTION: Do not connect the test fixture ground strapto any heat sink in this receiver.
Electrostatically Sensitive (ES) DevicesSome semiconductor (sol id-state) devices can be
damaged easily by static electricity. Such componentscommonly are called Electrostatically Sensitive (ES)Devices. Examples of typical ES devices are integrated
circuits and some f ield-effect transistors andsemiconductor "chip" components. The fol lowing
techniques should be used to help reduce the incidence ofcomponent damage caused by static by static electricity.
1. Immediately before h andling any semiconductorcomponent or semiconductor-equipped assembly, drainoff any electrostatic charge on your body by touching a
known earth ground. Alternatively, obtain and wear acommercially available discharging wrist strap device,
which should be removed to prevent potential shockreasons prior to applying power to the unit under test.
2. After removing an electrical assembly equipped withES devices, place the assembly on a conductivesurface such as aluminum foil, to prevent electrostatic
charge buildup or exposure of the assembly.3. Use only a grounded-tip soldering iron to solder or
unsolder ES devices.4. Use only an anti-static type solder removal device.
Some solder removal devices not classified as "anti-static" can generate electrical charges sufficient todamage ES devices.
5. Do not use freon-propelled chemicals. These can
generate electrical charges sufficient to damage ESdevices.
6. Do not remove a replacement ES device from itsprotective package until immediately before you are
ready to install it. (Most replacement ES devices arepackaged with leads electrically shorted together by
conductive foam, aluminum foi l or comparableconductive material).
7. Immediately before removing the protective materialfrom the leads of a replacement ES device, touch theprotective material to the chassis or circuit assembly
into which the device will be installed.CAUTION: Be sure no power is applied to the chassis
or circuit, and observe all other safety precautions.8. Minimize bodily motions when handling unpackaged
replacement ES devices. (Otherwise harmless motionsuch as the brushing together of your clothes fabric orthe lifting of your foot from a carpeted floor can
generate static electricity sufficient to damage an ESdevice.)
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General Soldering Guidelines1. Use a grounded-tip, low-wattage soldering iron and
appropriate tip size and shape that will maintain tip
temperature within the range or 500F to 600F.2. Use an appropriate gauge of RMA resin-core solder
composed of 60 parts tin/40 parts lead.3. Keep the soldering iron tip clean and well tinned.
4. Thoroughly clean the surfaces to be soldered. Use amall wire-bristle (0.5 inch, or 1.25cm) brush with a
metal handle.Do not use freon-propelled spray-on cleaners.
5. Use the following unsoldering technique
a. Allow the s oldering i ron tip to rea ch normaltemperature.
(500F to 600F)b. Heat the component lead until the solder melts.c. Quickly draw the melted solder with an anti-static,
suction-type solder removal device or with solder
braid.CAUTION: Work quickly to avoid overheating thecircuitboard printed foil.
6. Use the following soldering technique.
a. Allow the soldering iron tip to reach a normal
temperature (500F to 600F)b. First, hold the soldering iron tip and solder the strand
against the component lead until the solder melts.
c. Quickly move the soldering iron tip to the junction ofthe component lead and the printed circuit foil, and
hold it there only until the solder flows onto andaround both the component lead and the foil.
CAUTION: Work quickly to avoid overheating thecircuit board printed foil.
d. Closely inspect the solder area and remove any
excess or splashed solder with a small wire-bristlebrush.
IC Remove/Replacement
Some chassis circuit boards have slotted holes (oblong)through which the IC leads are inserted and then bent flatagainst the circuit foil. When holes are the slotted type,
the following technique should be used to remove andreplace the IC. When working with boards using the
familiar round hole, use the standard technique asoutlined in paragraphs 5 and 6 above.
Removal
1. Desolder and straighten each IC lead in one operation
by gently prying up on the lead with the soldering irontip as the solder melts.
2. Draw away the melted solder with an anti-staticsuction-type solder removal device (or with solderbraid) before removing the IC.
Replacement
1. Carefully insert the replacement IC in the circuit board.
2. Carefully bend each IC lead against the circuit foil padand solder it.
3. Clean the soldered areas with a small wire-bristle
brush. (It is not necessary to reapply acrylic coating tothe areas).
"Small-Signal" Discrete Transistor
Removal/Replacement1. Remove the defective transistor by clipping its leads as
close as possible to the component body.2. Bend into a "U" shape the end of each of three leads
remaining on the circuit board.
3. Bend into a "U" shape the replacement transistor leads.4. Connect the replacement transistor leads to the
corresponding leads extending from the circuit boardand crimp the "U" with long nose pliers to insure metal
to metal contact then solder each connection.
Power Output, Transistor Device
Removal/Replacement1. Heat and remove all solder from around the transistor
leads.2. Remove the heat sink mounting screw (if so equipped).
3. Carefully remove the transistor from the heat sink of thecircuit board.
4. Insert new transistor in the circuit board.
5. Solder each transistor lead, and clip off excess lead.6. Replace heat sink.
Diode Removal/Replacement
1. Remove defective diode by clipping its leads as closeas possible to diode body.
2. Bend the two remaining leads perpendicular y to the
circuit board.3. Observing diode polarity, wrap each lead of the new
diode around the corresponding lead on the circuitboard.
4. Securely crimp each connection and solder it.
5. Inspect (on the circuit board copper side) the solderjoints of the two "original" leads. If they are not shiny,
reheat them and if necessary, apply additional solder.
Fuse and Conventional Resistor
Removal/Replacement1. Clip each fuse or resistor lead at top of the circuit board
hollow stake.2. Securely crimp the leads of replacement component
around notch at stake top.3. Solder the connections.
CAUTION: Maintain original spacing between thereplaced component and adjacent components and thecircuit board to prevent excessive component
temperatures.
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Circuit Board Foil Repair
Excessive heat applied to the copper foil of any printedcircuit board will weaken the adhesive that bonds the foil
to the circuit board causing the foil to separate from or"l i f t-off" the board. The fol lowing guidel ines and
procedures should be followed whenever this condition isencountered.
At IC Connections
To repair a defective copper pattern at IC connections use
the following procedure to install a jumper wire on thecopper pattern side of the circuit board. (Use thistechnique only on IC connections).
1. Carefully remove the damaged copper pattern with a
sharp knife. (Remove only as much copper asabsolutely necessary).
2. carefully scratch away the solder resist and acrylic
coating (if used) from the end of the remaining copperpattern.
3. Bend a small "U" in one end of a small gauge jumperwire and carefully crimp it around the IC pin. Solder the
IC connection.4. Route the jumper wire along the path of the out-away
copper pattern and let it overlap the previously scrapedend of the good copper pattern. Solder the overlappedarea and clip off any excess jumper wire.
At Other Connections
Use the following technique to repair the defective copperpattern at connections other than IC Pins. This technique
involves the instal lat ion of a jumper wire on thecomponent side of the circuit board.
1. Remove the defective copper pattern with a sharpknife.Remove at least 1/4 inch of copper, to ensure that a
hazardous condition will not exist if the jumper wireopens.
2. Trace along the copper pattern from both sides of thepattern break and locate the nearest component that isdirectly connected to the affected copper pattern.
3. Connect insulated 20-gauge jumper wire from the leadof the nearest component on one side of the pattern
break to the lead of the nearest component on theother side.
Carefully crimp and solder the connections.
CAUTION: Be sure the insulated jumper wire isdressed so the it does not touch components or sharp
edges.
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TIMING CHART
VIDEO
SYNC
B
C
E
A
D
1 H(Pixels) + 25.175 31.469 800 640 16 96 48 640 x 350
V(Lines) - 70.09 449 350 37 2 60
2 H(Pixels) - 28.321 31.468 900 720 18 108 54 720 X 400
V(Lines) + 70.08 449 400 12 2 35
3 H(Pixels) - 25.175 31.469 800 640 16 96 48 640 x 480
V(Lines) - 59.94 525 480 10 2 33
4 H(Pixels) - 31.5 37.5 840 640 16 64 120 640 x 480
V(Lines) - 75 500 480 1 3 16
5 H(Pixels) + 40.0 37.879 1056 800 40 128 88 800 x 600
V(Lines) + 60.317 628 600 1 4 23
6 H(Pixels) + 49.5 46.875 1056 800 16 80 160 800 x 600
V(Lines) + 75.0 625 600 1 3 21
7 H(Pixels) +/- 57.283 49.725 1152 832 32 64 224 832 x 624
V(Lines) +/- 74.55 667 624 1 3 39
8 H(Pixels) - 65.0 48.363 1344 1024 24 136 160 1024 x 768
V(Lines) - 60.0 806 768 3 6 29
9 H(Pixels) - 78.75 60.123 1312 1024 16 96 176 1024 x 768
V(Lines) - 75.029 800 768 1 3 28
10 H(Pixels) +/- 100.0 68.681 1456 1152 32 128 144 1152 x 870
V(Lines) +/- 75.062 915 870 3 3 39
11 H(Pixels) +/- 92.978 61.805 1504 1152 18 134 200 1152 x 900
V(Lines) +/- 65.96 937 900 2 4 31
12 H(Pixels) + 108.0 63.981 1688 1280 48 112 248 1280 x 1024
V(Lines) + 60.02 1066 1024 1 3 38
13 H(Pixels) + 135.0 79.976 1688 1280 16 144 248 1280 x 1024
V(Lines) + 75.035 1066 1024 1 3 38
MODE H / V Sync
PolarityDot
Clock Frequency
TotalPeriod
( E )
VideoActive
Time ( A )
SyncDuration
( D )
FrontPorch( C )
BlankingTime( B )
Resolution
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DISASSEMBLY-Set
In assembly state, rotate stand body to upper side.
Remove the screws. 1. Pull the front cover upward.2. Then, let the all latches are separated.3. Put the front face down.
Disassembly Back Cover. Disassemble Connector.
# 1 # 2
# 4# 3
# 5
Pull the stand and separate stand from monitor set.
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DISASSEMBLY-Stand
In assembly state, rotate stand body to upper side. Pull the stand and separate stand from monitor set.
Pull four latchs each side the on stand body to outside.Consequently, rotate the stand body to reverse of pullingdirection.
Pull the stand body and separate the stand body from standbase.
# 1 # 2
# 4# 3
# 5
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BLOCK DIAGRAM
TSU
Mx6AL
A
DC
TMDS
Rx
M
StarACE
LVDS
Tx
LVDS
Analog(R/G/B)
D-Sub
LIPS
Filter
5V
12V
5V
3.3
V
1.8
V
Vcc
5V
5V
Scaler
MCU
Intel8032
Inve
rter(4lamps)
12V
Regulator
KEY
3.3
V
1.8
V
LineBuffer
OSD
SSC E
EPROM
(System)
Module
3.3
V
SDA
/SCL
3.3
V
FlashROM
12V
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BLOCK DIAGRAM-POWER
LAMP
High
Low
POWER
IN
VERTER
Inverter
Control
IC
P-ch
N-ch
Inverter
Trans
SMPS
Lamp
Current
Feedback
Over
Voltage
Protection
Power
Control
IC
Feedback
LineFilter
L
N
DriveBlock
12V
12V
5V
InverterOn/OFF(3.3
V)
Dimming(LampCurrentControl)
Aux
Drive
Start
ModuleVcc
MainBoard
(Scaler&
DCDC
converter)
12V
5V
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DESCRIPTION OF BLOCK DIAGRAM
1. Video Controller Part.
This part amplifies the level of video signal for the digital conversion and converts from the analog video signal to the
digital video signal using a pixel clock.
The pixel clock for each mode is generated by the PLL.
The range of the pixel clock is from 25MHz to 135MHz.This part consists of the Scaler, ADC convertor, TMDS receiver and LVDS transmitter.
The Scaler gets the video signal converted analog to digital, interpolates input to 1280 X 1024 resolution signal and
outputs 8-bit R, G, B signal to transmitter.
2. Power Part.
This part consists of the one 3.3V, and one 1.8V regulators to convert power which is provided 5V in Power board.
12V is provided for inverter, 5V is provided for LCD panel.
Also, 5V is converted 3.3V and 1.8V by regulator. Converted power is provided for IC in the main board.
The inverter converts from DC12V to AC 700Vrms and operates back-light lamps of module.
3. MICOM Part.
This part is include video controller part. And this part consists of EEPROM IC which stores control data, Reset IC and
the Micom.
The Micom distinguishes polarity and frequency of the H/V sync are supplied from signal cable.
The controlled data of each modes is stored in EEPROM.
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LIPS Board Block Diagram
EMI
COMPONENTSLINE100 ~ 240V
INPUT RECTIFIER
AND FILTER
SWITCHING
TRANSFORMER
OUTPUT RECTIFIER
AND FILTER
12V
5V
GND
SIGNALCOLLENT-
IONPHOTO-COUPLER
ISOLATION
PWM CONTROLCIRCUIT
HVDC 100KHz
PRIMARY SECONDARY
50 ~ 60Hz
INVERTER CIRCUIT High Voltage12V
Operation description_LIPS
1. EMI components.
This part contains of EMI components to comply with global marketing EMI standards like FCC,VCCI CISPR, the
circuit included a line-filter, across line capacitor and of course the primary protection fuse.
2. Input rectifier and filter.
This part function is for transfer the input AC voltage to a DC voltage through a bridge rectifier and a bulk capacitor.
3. Energy Transfer.This part function is for transfer the primary energy to secondary through a power transformer.
4. Output rectifier and filter.
This part function is to make a pulse width modulation control and to provide the driver signal to power switch, to
adjust the duty cycle during different AC input and output loading condition to achieve the dc output stabilized, and
also the over power protection is also monitor by this part.
5. Photo-Coupler isolation.
This part function is to feed back the DC output changing status through a photo transistor to primary controller to
achieve the stabilized DC output voltage.
6. Signal collection.
This part function is to collect the any change from the DC output and feed back to the primary through phototransistor.
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ADJUSTMENT
Windows EDID V1.0 User Manual
Operating System: MS Windows 98, 2000, XP
Port Setup: Windows 98 => Dont need setup
Windows 2000, XP => Need to Port Setup.
This program is available to LCD Monitor only.
1. Port Setup
a) Copy UserPort.sysfile to
c:\WINNT\system32\driversfolder
b) Run Userport.exe
c) Remove all default number
d) Add 300-3FF
e) Click Start button.
f) Click Exit button.
2. EDID Read & Write
1) Run WinEDID.exe
2) Edit Week of Manufacture, Year of Manufacture,
Serial Number
a) Input User Info Data
b) Click Updatebutton
c) Click Writebutton
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220
IBM
Compatible PC
PARALLEL PORT
Power inlet (required)
Power LED
ST Switch
Power Select Switch(110V/220V)
Co
ntrolLine
Not
used
RS232C
PARALL
EL
V-SYNC
POWER
ST
VGS
MONITOR
E
E
V-Sync On/Off Switch
(Switch must be ON.)
F
F
A
A
BB
C
C
15
10
5
5
69
1
1
1
14
13
25
6
5V
5V
5V
4.7K4.7K
4.7K
74LS06
74LS06
OFF ON
OFF
ON
11Video SignalGenerator
Figure 1. Cable Connection
SERVICE OSD
1) Turn off the power switch at the front side of the display.
2) Wait for about 5 seconds and press MENU, POWER switch with 1 second interval.
3) The SVC OSD menu contains additional menus that the User OSD menu as described below.
a) Auto Color : W/B balance and Automatically sets the gain and offset value.
b) NVRAM INIT : EEPROM initialize.(24C08)
c) CLEAR ETI : To initialize using time.
d) AGING : Select Aging mode(on/off).
e) R/G/B-9300K : Allows you to set the R/G/B-9300K value manually.
f) R/G/B-6500K : Allows you to set the R/G/B-6500K value manually.
g) R/G/B-Offset : Allows you to set the R/G/B-Offset value manually.(Analog Only)
h) R/G/B-Gain : Allows you to set the R/G/B-Gain value manually.(Analog Only)
i) MODULE : To select applied module.
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TROUBLESHOOTING GUIDE
1. NO POWER
NO POWER
(POWER INDICATOR OFF)
NOCHECK POWER BOARD,AND FIND OUT A SHORT
POINT AS OPENINGEACH POWER LINE
NO PROBLEM
1Waveforms
U201-#96
CHECK KEY CONTROLCONNECTOR ROUTINE
CHECK U201
NO
NO
CHECK 3.3V LINE(OPEN CHECK)
CHECK 3.3V LINE
NOCHECK X-TAL
YES
CHECK J403VOLTAGE
PIN5, PIN6 (5V)?
CHECKU301 PIN2 VOLTAGE
(3.3V) ?
IS U201PIN75 (3.3V)VOLTAGE ?
CHECK U201 PIN 96PULSE
1
YES
YES
YES
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2. NO RASTER (OSD IS NOT DISPLAYED) LIPS
NO RASTER
(OSD IS NOT DISPLAYED)
NO
NO
NO
NO
REPLACE CCFL LAMPIN THE LCD MODULE
CHECK POWER BOARD,AND FIND OUT A SHORTPOINT AS OPENING EACHPOWER LINE
CHECK MICOM INVON/OFF PORT.
1. CONFIRM BRIGHTNESSOSD CONTRL STATE.
2. CHECK MICOM DIM-ADJPORT
LIPS
J403PIN5, PIN6
5V?
J403 PIN9
5V?
J403 PIN105V?
CHECKPULSE AS
CONTACTING SCOPEPROBE TO CAUTION LABEL.
(CONTACT PROBE TOCAUTION LABEL.
CAN YOU SEE PULSEAT YOURSCOPE?
YES
YES
YES
YES
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3. NO RASTER (OSD IS NOT DISPLAYED) MSTAR
NO RASTER
(OSD IS NOT DISPLAYED)
NO
NO
NO
TROUBLE IN CABLEOR LCD MODULE
CHECK U301
1. CHECK C210, C211SOLDERING CONDITION
2. CHECK X2013. TROUBLE IN U201
CHECK CONNECTIONLINE FROM D-SUB TOU201
U201PIN96, 97
OSCILLATE AS14.31MHZ?
U201PIN27 IS 48KHz H-SYNC?PIN28 IS 60Hz V-SYNC?IS PULSE APPEARED
AT SIGNAL PINS?AT MODE 12?
1
2
1 2
WaveformsU201-#96, 97 U201-#27 H-SYNC 2 U201-#28 V-SYNC
YES
YES
YES
U201PIN 16, 75
3.3V?
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4. TROUBLE IN DPM
TROUBLE IN DPM
NO
NO
TROUBLE IN U201
CHECK PCPC IS NOT GOINGINTO DPM OFF MODE
CHECK H/V SYNC LINE
CHECKR442, R443
CHECKU201 PIN 27,28SYNC PULSE ?
3
3
Waveforms
R442 H-Sync 3 R443 V-Sync
YES
YES
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5. POWER
NO POWER
(POWER INDICATOR OFF)
NOTrouble in Fuse (F101)
CHECK 5V, 12V Line
NO
NO
Check BD101
Check U101 Pin7 : 9~10VCheck D102
Trouble in Q101
NOTrouble in D201, D202
YES
CHECKFuse F101 OK?
CHECKC101 Voltage
(AC110V->160Vdc(AC220V->304Vdc
CHECKU101 Pin6 Waveform
(Square waveCome out?)
Check Q101 DrainWaveform
Check D201, D202Voltage
YES
YES
YES
YES
NO
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6. Raster
NO Raster
(Lamp Off)
NO Check Scaler Output(Main Board)
CHECK T301, T302
NO
NO
Check Q301, Q302
Check the waveform of U301Pin11, 12, 19, 20
Check the waveform of U301Pin11, 12, 19, 20
NO
If waveform is no problem
Check Q303~Q308Or Trouble in U303, U304
YES
CHECKP201 Pin9
3.3V?
Check U301 Pin35V?
Check U301 Pin2 OVP,
Less than 1.8V
Check U301 Pin10 CMP,Less than 2.75V
Check U303, U304Drain waveform
YES
YES
YES
NO
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WIRING DIAGRAM
11P
6P
3P
30P
6631900011H
6631T20023J
6631900109A
6631T20010E
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EXPLODED VIEW
010
020
080
090
10
0
110
030
190
180
170
140
050
040
160
060
070
120
130
150
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SCHEMATIC DIAGRAM
- 29 -
1. SCALER
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2. POWER & WAFER
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3. INVERTER
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- 32 -
4. POWER
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Aug. 2006P/NO : 38289S0041 Printed in Korea